The present invention relates to a dies exchanging device for machines using dies such as vertical presses, horizontal injection molding machines or die-casting machines. However, this device is applicable as a work-pallet exchanging device for machine tools.
As typical examples of conventional dies exchanging devices for such machines using dies are known "press dies transfer device" as shown in FIGS. 13 and 14.
This press die transfer device consists in that a pair of carriage cars 205 are movable in front of the press, two die mounting sections are provided on the carriage car 205, a push-pull device P1 is provided in front of die mounting sections and on one side of each carriage car 205, a chain 212 driven by a sprocket 223 of a driving means is guided along a guide groove in a guide member 214 of the carriage car 205 so restrained lest it should bend and a push-pull hook means 213 connected to the forward end of the chain 212 is used to advance or retract dies D1 for exchanging thereof.
In this device the push-pull device P1 is provided for each of the two carriage cars 205, and only one unit of the push-pull device is operative as the dies are exchanged, the other unit of the device is always kept idle.
Moreover, since the whole push-pull device is incorporated in the carriage car 205, the construction of the carriage car 205 is complicated, its weight is increased and the travelling gear becomes bulky.